Fix snapshot clippy lints (#685)

The sixth in a series of PRs that aim to get CI passing

src/snapshot/patch_apply.rs

@@ -97,8 +97,7 @@ fn finalize_patch_application(context: PatchApplyContext, tree: &mut RojoTree) -
 
         for value in instance.properties_mut().values_mut() {
             if let Variant::Ref(referent) = value {
-                if let Some(&instance_referent) = context.snapshot_id_to_instance_id.get(&referent)
-                {
+                if let Some(&instance_referent) = context.snapshot_id_to_instance_id.get(referent) {
                     *value = Variant::Ref(instance_referent);
                 }
             }

src/snapshot/patch_compute.rs

@@ -26,10 +26,8 @@ pub fn compute_patch_set(snapshot: Option<InstanceSnapshot>, tree: &RojoTree, id
         // for all of the IDs that we know about so far.
         rewrite_refs_in_updates(&context, &mut patch_set.updated_instances);
         rewrite_refs_in_additions(&context, &mut patch_set.added_instances);
-    } else {
-        if id != tree.get_root_id() {
-            patch_set.removed_instances.push(id);
-        }
+    } else if id != tree.get_root_id() {
+        patch_set.removed_instances.push(id);
     }
 
     patch_set

src/snapshot/tree.rs

@@ -37,8 +37,8 @@ pub struct RojoTree {
 
 impl RojoTree {
     pub fn new(snapshot: InstanceSnapshot) -> RojoTree {
-        let root_builder = InstanceBuilder::new(snapshot.class_name.to_owned())
-            .with_name(snapshot.name.to_owned())
+        let root_builder = InstanceBuilder::new(snapshot.class_name)
+            .with_name(snapshot.name)
             .with_properties(snapshot.properties);
 
         let mut tree = RojoTree {
@@ -245,7 +245,7 @@ impl<'a> InstanceWithMeta<'a> {
     }
 
     pub fn metadata(&self) -> &'a InstanceMetadata {
-        &self.metadata
+        self.metadata
     }
 }
 
@@ -294,6 +294,6 @@ impl InstanceWithMetaMut<'_> {
     }
 
     pub fn metadata(&self) -> &InstanceMetadata {
-        &self.metadata
+        self.metadata
     }
 }